slow neutron

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slow neutron

n
(General Physics) physics a neutron having a kinetic energy of less than 100 electronvolts
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In 1938 he received the Nobel Prize in Physics "for his demonstrations of the existence of new radioactive elements produced by neutron irradiation, and for his related discovery of nuclear reactions brought about by slow neutrons" (1, 2).
Roulier, "Probing strongly coupled chameleons with slow neutrons," Physical Review D, vol.
If D or T molecules are combined chemically with one oxygen atom we get heavy water which is used as stopper of fast neutron in fission reactors, so that fissionable uranium ( ) can be broken by the stopped neutrons usually known as slow neutrons. In ordinary hydrogen atom the minimum possible constant distance between proton and the revolving around it electron is 10-8cm, usually know as s-wave approximation or Bohr's first orbital radius also know as K-shell radius.
Nuclear weapons require fissile material, atoms of which can fission (split) when struck by fast or slow neutrons (4); pieces of this material can support a nuclear chain reaction.
In a recent paper (1) the reaction of slow neutrons with gasous [.sup.3]He was studied experimentally and it was estimated that that in the experiment 46 Lyman alpha photons were produced for each slow neutron (wave-length 0.496 nm) absorbed in a chamber containing [.sup.3]He at a pressure of 93 kPa.
After high energy neutrons are emitted by the source and diffuse outward through the soil, a fraction of the slow neutrons rebound back towards the probe and are absorbed by the nucleus of the gas in the detector, giving rise to a signal that, after processing, is known as the `neutron count'.
That's when spring will arrive in the region and a top layer of carbon dioxide frost will evaporate, opening a path for slow neutrons from underlying material to reach the spacecraft's detectors.
Since the bulk cross section of slow neutrons interacting with hydrogen is much larger that of deuterium, the transmission (i.e.
Plutonium 239, being fissionable with slow neutrons, can be used as a fuel in power plants, but it can also be used in nuclear weaponry.
In 1938, Otto Hahn and Fritz Strassmann used slow neutrons to effect the first experimentally induced fission of uranium.
Fermi had bombarded uranium with slow neutrons in the hope of obtaining element number 93, but the results had been confusing (see 1934).